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How to configure an ASA with 2 Public IP address.

Hi, I have to configure a router ASA 5505 with 2 Publics IP, our ISP give us a 3 Public IP, and actually our configuration is like this:


interface Vlan1

nameif inside

security-level 100

ip address 192.168.x.x


interface Vlan2

nameif outside

security-level 0

ip address 200.91.x.x



The problem is: If I create a new Vlan, the interface overlaps.

How can I solve that problem??

Thanks for your answers!!!

Everyone's tags (1)
Hall of Fame Super Silver

You'd get better visibility

You'd get better visibility in the Firewall forum, but I can answer your question.

Typically when you have multiple addresses from a given subnet (as you imply), the additional ones are used for services that you want to setup with static NAT addresses.

The first one is, for instance, the interface Vlan 2 address and the global dynamic NAT for all outgoing traffic.

A second one could be a static NAT for incoming traffic to a server - for instance it could be for your internal email server and you would have a static NAT and an access-list entry allowing incoming traffic on tcp/25 (smtp) or - for Outlook web Access for example - tcp/443. that second (and third etc. ) address is not assigned to an interface under the interface configuration but rather via the NAT rule. (e.g. nat (inside,outside)___"